1. Field of the Invention
The present invention relates to a power converting mechanism, and more particularly, to an inverter capable of determining an output frequency of the inverter according to a frame switch signal and a method for controlling the output frequency of the inverter.
2. Description of the Prior Art
For a liquid crystal display (LCD) with a direct-light type backlight module, because lamps in the backlight module are driven by a high voltage signal (about 1000 volts), a so-called “waving” phenomenon occurs to displayed images due to electro-magnetic interference (EMI) generated by the lamps and an inverter. Generally, the “waving” phenomenon resembles several horizontal bands, and positions of the horizontal bands are related to an output frequency of the inverter (i.e., a driving frequency of the lamps). Therefore, if the inverter outputs a fixed output frequency, the horizontal bands occur at almost the same positions on the screen, and are easily sensed by the user. The fixed output frequency outputted from the prior art inverter therefore causes the quality of the displayed image to be degraded.